Shock absorber



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4 'sheets-sheet C. W. SHERMAN ET AL SHOCK ABSORBER Filed May 27, 1925 July 15, 1930.

July 15,. 1930.` c. w, SHERMAN ET AL SHOCK ABSORBER 4 sheets-sheet' v3 Filed May 27, 1926 July 15, T930' C. w. SHERMAN Er AL SHOCK ABSORBER Filed May 27, 192.6

4 Sheets-'Sheet bined spring seat and release P. su

Patented July 15, 1930 vli ETSEB STTES CLFTGN W'. SHERMAN AND JOSEPH M. HALL, 0F HAMILTON, ONTARIO, CANADA, AS- ySIGNORS TO HALL. DRAFT GEAR CORPRATION, F BUFFALC,T.TEW YORK, A COR- PORATION 0F NEW' YORK SHOCK Ansoannn Application filed May 27, 1926. Serial No. 1l1,979.

`This invention relates to a shock absorber which is more particularly intended for use in vdraft gears or riggings of railway cars Aand siinilar installations, when heavy shocks areto be cushioned and which is of the type employing a plurality of'intercalated friction plates in addition Yto a springk resist-ance.

One of the .objects of this invention is to materially increase the frictional area and also increase somewhat, thespringfresistance and thus permit of increasing the shock absorbing capacity of the gear and still reduce the work `done `by the friction plates per square of surface, by distributing the saine over a greater area.

Another objectof this invention is to dispense with castings, housings or the like around the spring systeni and friction plates Figure l is a horizontal section of a shock i absorber embodying one forni of our invention. Y Y

Figure 2 is a cross-section of the same taken on line 2-2 Fig. l;

Figures 3, d and 5 are perspectiveV views of a wedge block, a wedge shoe, and a coinbar forming part of this invention. Y Y x Figurest and 7 are vertical longitudinal sections taken on the correspondingly num'- bered lines in Fig. l. Figure 8 is a horizontal section of a slightly modified forni of our iniproved shack absorber. v Y y Figure 9 is cross-section ofthe saine taken en line l-S), Fig. 8. .A

Figure l0 is a horizontal scct'ioinshowing another modification of our invention.

Figure 1l is a vertical longitudinal section taken on line ll-fll, Fig. 10.

Siniilar characters of reference indicate like parts in the several figures of the draws ings:

Referring to the structure shown in Figs. 1 7, the nunierals 20, 20, represent the longitudinalisills or bea-ins `which are part of the inain fraine of the ear,and which in the presentvinstancc are constructed in the` forni of channel irons having their channels facing Vlaterally outward. .s Arranged lengthwise on the inner sides of the sills and adapted to engage frictionally therewith are the two longitudinal straps, bars or platesv 2l, E21 which fcrn'i parts of the draft yoke and are coupled with the shank or butt22l of the coupler 23 which is arranged between the front parts of the straps by a vfront coupler lrey 2d passing transversely through an epe ing 25 in the rear end of' the butt, and also through Vopenings 26 in the front ends ofthe yoke straps, as shown in Figs. l, 6 and `The opposite ends of the front key 24 also pass through longitudinal slots 7, in the ad` jacent part of the car sills. The edges of these slots are lined by cheek plates or castings 28, secured to the outer sides of the sills forthe purpose of reinforcing the saine, i

thereby 'forming a support, and longitudinal guides for the coupler 23 and the `front ends of the draft yoke strapsl.

Adjacent to the innerv side ofeach yoke strap are arranged two sets of iiitercalated friction plates 29, 30, each of which has an outer y.longitudinal slot 3l at its outer end and an inner longitudinal slot at its inner end and an intermediate longitudinal slot acent to its outer end. At the front and rear eiidscf'the several sets of friction plates, thesanie are'engaged on their inner sides by front and rear wedge shoes 34:, 35,e`ach of which is provided at its longitudinal edges with longitudinal reinforcing flanges 19.

Wlidway of the iniierside of each wedge shoe th saine is providedfwith a transverse rib, having an inwardly facing incline 86 and an outwardly facing incline `Si',y and von its vcentral part the saine is provided withv a central longitudinal slot 38 and at its outer end with an outer slot 39. i

The numerals 40, 4l represent front and rear wedge blocks which are arranged respectively between the front and rear pairs of wedge shoes and each of which is provided at its inner end with inwardly converging inclines or faces 42 which engage respectively with the outwardly diverging inclined faces 37 of the adjacent pair of wedge shoes. .'lhe front wedge block in the relaxed condition of the gears, engages its outer end with the rear end of the coupler butt and the outer end of the rear wedge block engages a stop block 43, secured to the opposing inner parts of the car sills. Each of the wedge blocks has its horizontall opposite sides arranged between the inwar 1y projecting flanges 19 of the adjacent wedge shoes, as shown in Figs. 1, 2 and 3, thereby guiding these parts relatively to each other.

The numerals 44, 45 represent front and rear thrust ke s or bars, the front one passing transverselj through a slot 46 in the front wedge blocks and the slots 39, 31, 32 of the adjacent wedge shoes, and friction plates and also through intermediate .longitudinal slots 47 in the yoke straps and intermediate slots 48 in the car sills, which latter are also lined and reinforced by the cheek plates 28. The rear thrust key passes through a slot 46 in the rear wedge block and through the outer slots 39 of the adjacent wedge shoes and the slots 31, 32 of the friction plates, and also through rear longitudinal slots 49 in the yoke straps and rear longitudinal slots 50 in the car sills, which latter are also lined and reinforced by the cheek plates, as shown in Fig. 1.

Adjacent to the outer sides of the car sills are the members of the releasing spring system which in its preferred forin consistso two longitudinal clusters comprising an inner s ring 51 and an outer spring 52 surroun ing the inner spring, and both springs bearing at o posite ends against cup-shaped heads or sockets 53 which are connected by vertical pins 541 to the adjacent outer ends of the front and rear thrust keys.

Adjacent to the inner ends of the front and rear wedge blocks are front and rear spring seat 54, 55 each of which is provided at its transversely opposite edges with outwardly converging inclines or wedge faces 56, which engage with the inwardly diverging inclines 36, 36, on the adjacentpair of wedge shoes, as shown in Fig. 1. Qn its outer side each spring seat is provided with a transverse releasing bar 57 preferably formed inall therewith and engaging its central part with a notch 58 in the inner end of the adjacent wedge block and projecting with its opposite ends through the central slots 38 of the adjacent wedge shoes and the adjacent slots`32, 33 of the `friction plates.

interposed between the two spring seats and arranged centrally between the two pairs of friction plates and wedge shoes, is a main thrust spring system which resists movement of the wedge blocks and associated parts, one lengthwise relatively to another which thrust spring system preferably consists of an in ner s ring 59 and an outer sprin 60 surroun ing the inner spring and bot i springs bearing against the inner side of the central spring seats, as shown in Figs. l and 6.

Those parts of the car sills upon which the shock absorber is mounted are connected at the to i or upper side by a top retaining plate 61 an at the bottom or underside by a bottoin retaining plate ($2, which plates may be riveted to the tianges of the sills as shown in Fig. 2, or secured by any other suitable means. The plates hold the sills against spreading under the stress of the block absorber when the same is subjected to a load and retain the parts in their proper relative position.

, The operation of this shock absorber is as follows:-

lVhen the shock absorber is in its fully relaxed or released position, the springs forniing the spring resistance are under an initial compression which is effected prior to coinpleting assembling of the parts, and when thus fully relaxed, the front and rear friction plates, wedge shoes, wedge blocks and thrust keys are drawn apart their fullest extent, the front thrust keys engage with the front ends of the sill slots 48, the rear thrust keys engage with the rear ends of the rear sill slots 50, the rear wedge block bears against the rear stop, and the outer sides of the releasing bars engage with the outer ends of the outer slotsI 31 in the friction plates, as shown in Figs. 1, 6, 7.

If a buliing force is applied to the coupler suiiicient to overcome the initial resistance of the draft gear caused by the initial coinpression of the springs, and the friction-al i'esistance set up between the several friction plates by the Wedge actions of the blocks, shoes and spring seats; the front thrust. keys and front wedge block move ii'iwardly :ind the wedge shoes are caused to slide on the friction plates at both ends of the draft geur independently of the friction plates until the front thrust key engages with the inner ends of theiouter slots 31. in the front sets of friction plates, thereby causing the several intercalated sets of friction plates to be more tightly pressed together transversely of their length by the cooperating iiicliiies of the wedge blocks, wedge slices and central spring seats. The ,instant the front thrust key engages the inner ends of the slots 31 in the front sets of friction plates, the latter begin to move rearwardly and by frictional engagement with the rear sets of friction plates, the latter are also moved rearwardly until the inner ends of the outer slots in the rear sets of friction plates engage with the inner edge Dof the rear thrust lre. lifter this, the rear sets of friction plates are held stationary and vthe front set-sof friction plates are caused to slide rearwardly on the rear sets of friction plates as the buiiing load overcomes the progressively increasing fricticnal and spring resistance of the friction pilates,l and the springs of the main thrust and the releasing spring systems, thereby'gradually checl-:ing

the movcmentof the bufling load and absorbing the saoclr so as to avoid injurious actions on the car and its cargo, or discomfort `to the passengers which are being carried.

TWhenv the buiiing load on the shock absorber is relieved to such an extent as will allow the release springs t'o'fforce the frorl thrust lrey forwardly, these springsiirst tend to relieve the wedging action on the wedge shoes.

The pressure of the main thrust spring system, which is under compression, still forces the front spring seat the front wedge y shoes and tends to holdthe latter in wedging engagement therewithuntilthe outer edge of A the front releasing bar 'is forcedinto contact with 'he outer ends of the outer slots 3l in the front setsI of friction plates.

aressure ofthefmainthrust spring is then divided between causing a wedgingaction on the wedge shoes and a retractive action on the ,friction plates` at which tinievthe 'releasing spring lsystem also tends to force the front thrust key forwardly to relieve the wedge action of the wedge shoes.

lilhen the front'thrust key engages the Vouter ends of the intermediate sill slots l vthe outward or forward movement of the vfront sets ofthe friction plates is arrested.

y During thisforward movement of the front sets of friction plates the rear sets move therewith until the outer ends 'of the outer slots 3l in the rear sets of friction plates engage 'the outer edge of the rear thrustv hey after o which the rear sets of friction plates are held and the, front sets move forwardly independently of the rear sets butY still. in sufficient frictional engagement therewith to prevent unduly quicl: or free release of the gear upon removal of the buliing load.

Upon subjecting the shock absorber to va pulling action the operation'is substantially the same as that liust described excepting that the frontthrust keyY remains stationary and A'the rear thrust ltey andwedge bloelr are moved forwardly with the coupler by means of the yoke straps Vwhich connect the rear thrust lifey with the coupler. y

Euring a buiiingaction the` yoke straps slide on the rear thrust key and during a Apulling' action these straps slide on the front thrust key, but during both of these actions,

the yoke straps are grippedfrictioiiallylbetween the inner sides of the car sillsand the outerV sides of the resoective sets'ofvfriction plates, wherebythese yoke straps, in ellect,

The

become a part of the friction system and aid in absorbing shock.

By these means the frictional yresistance `area of the absorber is materially increased, t the work done-per square/inch of friction area is greatly reduced and the capacity of the absorber is also increased.

Moreover, by reducing the amount of rwork done per square inch of area, due to distributing over a greater area, the wear upon the plates is reduced and the cost of replacement lessened accordingly.

If desired, the yoke straps may be arranged outside of the car sills, as shown at i211 in Figs.A 8 and 9, and the friction plates may engage directly with the inner sides of thc car sills as shown in same figures, in which case these straps perform the same function as those shown in Figs. l, 2, G, '7 with the exception thaty they do not contributey any friction area to aid in the absorption of shock; and the description of the method of operation with reference to the structure shown in Figs. l, 2, 6 and 7 therefore applies to that shown in Figs. 8 and 9.

instead of connecting the coupler with the thrust lreys, as shown in Figs. 1-9, for operating the shock absorber, substantially the same 'effect may be produced by employing yoke which connects the coupler with the rear wedge block, and which as shown by full y o connecting the upper and lower yoke straps 212 with the coupler consists of a vertical o coupling pin 2l5 passing through the-coupler butt and perforated lugs 216 arranged at the front ends of the straps 212, as shown by dotted lines in Figs. 10 and 11. y

rThe practical operations of the structure shown in Figs. 10 and l1 are substantially like that described with reference to the structure shown in Figs. 1 9.

i It will benoted that in this device the draft sills and cover plates connecting the same form,in eifect, a friction casing; the straps or links4 2l serve as draft members as well as friction members; and the` wedge elements also serve as followers.

We claim as our invention:

l. A shock kvabsorber.comprising a casing consistingof longitudinal sills forming part of a car body and transverse plates connected with saidesills; a plurality of sets ofstraight "longitudinal, intercalated friction #plates arlili.)

ranged within said casing and cach set movable lenf'thwise relatively to the other; wedge means fir pressing said friction plates laterally against said sills; a draft means for causing said wedge means to exert lateral outward pressure against said friction plates and sills, and a spring resistance which opposes the movement of said draft means against said wedge means.

2. A shock absorber comprising a casing consistingof longitudinal sills forming part of a car body and transverse plates connected with said sills; draft means including longitudinal yoke straps engaging with the inner sides of said sills; a plurality of sets of intercalated longitudinally movable straight friction plates arranged within the casing and between said yoke straps and each set movable len 4hwise relative to the other; wedge means or pressing said friction plates laterally outward against said yoke straps and pressing said oke straps laterally outward against said sills; draft means for shifting said yoke straps lengthwise and causing said Wedge means to act; and spring means for resisting longitudinal movement of said wedge means under the action of said draft means.

3. A shock absorber comprising a casing having longitudinal sills provided with longitudinal slots and transverse plates connecting said sills; a plurality of sets of longitudinal intercalated straight friction plates arranged between said sills and lcro-acting therewith each set movable lengthwise relatively to thevother and provided with longitudinal slots; wedge means for pressing said friction plates laterally outward toward said y sills and including lwedge shoes engaging with the inner longitudinal side of said sets of friction plates and wedge blocks havin wedgfingengagement with said wedge sioes, a

spring resistance opposing movement of said wedge means; transverse keys passing through said wedge blocks, friction plates i and sill slots; draft means for shifting said Wedge blocks, and friction plates lengthwise i and spring means engaging the outer ends of said keys.

4. A shock absorber comprising a casing having longitudinal sills provided with longi- 7 tudinal.' yslots and transverse plates connecting said sills; a plurality of sets of longitudinal intercalated straight friction plates arran ed between said sills and co-acting therewit each set movable lengthwise relatively to the other and provided with longitudinal 1slots; wed e means for pressing said friction lates aterally outward toward said sills and including wedge shoes engaging with the inner longitudinal side of said sets ofy friction plates and wedge blocks having wed ing engagement with said wedge shoes; eys mounted on said wedge blocks and passing through said slots; a releasing spring means engaging the outer ends of said keys; and

main spring means for moving said friction plates apart after compression.

5. A shock absorber comprising a casing consisting of longitudinal sills having longitudinal slots and transverse plates connecting said sills; a plurality of sets of intercalated longitudinal straight friction plates each set movable lengthwise relatively to the other end provided with inner and outer longitudinal slots; wedge means for ressing said friction plates laterally outward) and including wedge shoes engaging with the inner sides of said sets of friction lates sind longitudinally movable wedge locks engaging with said wedge shoes; keys passing transversely through said wedge blocks, the outer slots in said friction plates and the slots in said sills; releasing s rings interposed between tlie ends of said cys; return members engaging with the inner slots of said friction plates; and main spring means interposed between said return members.

6. A shock absorber comprising a casin having longitudinal sills provided with longit-udiiial slots and transverse plates connect-l ing the sills; yoke straps engaging with the inner longitudinal sides of said sills and provided with longitudinal slots; a plurality of sets of intercalated longitudinal straight friction plates engaging with the inner longitudinal sides of said yoke straps, each set movable lengthwise relative to the other and having inner and outer lon itudinal slots; wedge means for ressin sai friction plates laterally outward) and iaving wedge shoes engaging with the inner side of said sets of friction plates and longitudinally movable wedge blocks engaging with said wedge shoes; thrust keys passing transversely throu h said wedge blocks, the outer slots of the riction plates and the slots in the sills; release s ring means interposed between the ends o said keys; release bars passing through said wedge blocks, wedge shoes and the inner slots of said friction plat-es and having spring seats between said wedge shoes; and a main spring interposed between said spring seats.

7. A shock absorber comprising a casing having longitudinal sills provided with longitudinal slots and transverse plates connecting the sills; yoke straps engaging with the inner longitudinal sides of said sills and provided with longitudinal slots; a lurality of sets of intercalated longitudinal straight friction plates engaging with the inner longitudinal sides of said yoke straps, each set movable lengthwise relative to the other and having inner and outer -longitudinal slots; Wedge means for pressing said friction plates laterally outward and having wedge shoes engaging with the inner side of said sets of friction plates and longitudinally movable wedge blocks engaging with said wedge shoes; thrust keys passing transversely through said wedge blocks, the outer slots of the friction plates and the slots in the sills; release spring means interposed between the ends of said keys; release bars passing through said wedge blocks, wedge shoes and the inner slots oi' said friction plates and having spring seats between said wedge shoes; a main spring interposed between said spring seats, a coupler butt engaging one of said wedge blocks; and a key passing through said coupler butt and yoke straps and guided on said sills.

In testimony whereof we, hereby aiiix our signatures. f

CLIFTON W. SHERMAN. JOSEPH M. HALL. 

